The instant system is concerned with the application of insulated panels to storage tank structures. More particularly it is concerned with a system for securing insulated panel sections to storage tanks which constitutes an improvement over the tank jacketing system disclosed and described in Schroter U.S. Pat. No. 4,044,517 issued Aug. 30, 1977. As indicated in the aforesaid Schroter patent, various arrangements or systems have been devised in the past for securing insulated panels of the type shown and discussed in U.S. Pat. Nos. 3,312,028 and 3,555,758 to storage tanks including the systems disclosed in a current brochure of the Owens-Corning Fiberglas Company entitled "Zip-Rib Tank Insulation System" published in June, 1975. While the system proposed in the Schroter patent has been found to be generally satisfactory it still has certain deficiencies as regards the costs of parts used and the time and labor required for installation.
The instant development is concerned with providing a more simplified system for anchoring insulated panel sections to a tank by means of anchoring bands and articulated fasteners. These fasteners are self adjusting under various loads whereby they accommodate themselves in an improved fashion to variations in the dimensions of the tank due to different temperatures and loading conditions while maintaining tight contact with the individual panel sections. Under normal service conditions oil and water storage tanks expand and contract with changes in temperature and hydrostatic pressures resulting from filling and emptying the tanks with liquids, etc., and the larger the tank the greater range of temperature and pressure variation.
Most storage tank exterior panel anchoring band systems, as indicated in prior art U.S. Pat. No. 2,955,686 to Blomeley et al and U.S. Reissue Pat. No. 27,330 to Marcmann, accommodate themselves to the expansion and contraction of the tanks through the use of spring loaded fastener devices. These spring loaded fastener devices are located at spaced intervals about the outside of the tank and as the tank swells or expands from heat or pressure, these fastener devices allow the panel anchoring bands to expand or contract without going slack or becoming over stressed. A drawback of such systems, however, is that the movement of the panel anchoring bands usually takes place at spaced intervals and there is relative horizontal movement and wear of the bands at all other points along the circumference of a tank equipped with such systems. In the panel band anchoring system of the aforementioned Schroter patent the tension bands mounted under the insulated panels generally experience the same thermal change as the tank so that no accommodation for thermal expansion is ordinarily required and there is little or no relative movement of the panel anchoring band elements and the insulation jacket provided by the panels.
There are occasions, however, in exteriorly jacketed storage tank structures, where expansion from the hoop stress in a loaded tank can introduce harmful stresses in the anchor bands which in turn diminish the useful strength of the bands used to secure the jacketing formed from insulated panels to the tank wall. By utilizing stranded wire cables in lieu of solid steel bands or tracks and the instant improved articulated fasteners for securing the panels to the cables during application of a jacketing system to a tank, the tank and wire cables will expand substantially uniformly relative to each other with the result that no undue stresses or movements will be imposed on the jacketing system and the components thereof.
The instant tank jacketing anchoring system also constitutes an improvement over those disclosed in the prior art patents noted in the aforementioned Schroter patent as well as those described in U.S. Pat. Nos. 2,355,947; 2,442,977; 3,339,778; 3,154,889; 3,174,591; 3,562,987; 3,555,758 and 3,572,000.